<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app"></div>
    <template id="my-app">
        <h2>{{count}}</h2>
        <h1 v-once>{{count}}</h1>
        <!-- v-once指令，只渲染一次，后续数据变化，视图不会更新 -->

        <button @click="add">+1</button>
    </template>

    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <script>
        const App = {
            template:'#my-app',
            data () {
                return {
                    count:100
                }
            },
            methods:{
                add(){
                    this.count++
                }
            }
        }
        Vue.createApp(App).mount('#app')
    </script>
</body>
</html>